Depressing, especially since it’s based on a huge sample. The key, of course, is correlation: It’s not whether white Democrats have negative opinions about blacks that matters (for these purposes), it’s the extent to which those opinions influence how they’re voting. What the poll’s trying to do, in essence, is untangle racial prejudice from the knot of hundreds of other considerations that go into one’s choice. Whether that’s possible, particularly via an unusual methodology that attempts to account for unconscious racism — note the details about “affect misattribution” and lists of things people find “upsetting” — I leave to our statistician readers to decide. The gist:

More than a third of all white Democrats and independents — voters Obama can’t win the White House without — agreed with at least one negative adjective about blacks, according to the survey, and they are significantly less likely to vote for Obama than those who don’t have such views…

Lots of Republicans harbor prejudices, too, but the survey found they weren’t voting against Obama because of his race. Most Republicans wouldn’t vote for any Democrat for president — white, black or brown.

Not all whites are prejudiced. Indeed, more whites say good things about blacks than say bad things, the poll shows. And many whites who see blacks in a negative light are still willing or even eager to vote for Obama.

On the other side of the racial question, the Illinois Democrat is drawing almost unanimous support from blacks, the poll shows, though that probably wouldn’t be enough to counter the negative effect of some whites’ views.

Race is not the biggest factor driving Democrats and independents away from Obama. Doubts about his competency loom even larger, the poll indicates. More than a quarter of all Democrats expressed doubt that Obama can bring about the change they want, and they are likely to vote against him because of that…

Still, the effects of whites’ racial views are apparent in the polling.

Statistical models derived from the poll suggest that Obama’s support would be as much as 6 percentage points higher if there were no white racial prejudice.

There’s so much data to digest that I’m inclined to treat this as an open thread and let you guys mine the crosstabs in the comments. A few observations, though:

1. We already had a clue about this from the primaries, per the exit polls from Ohio. Fully 20 percent admitted race mattered to their vote; of those, almost 60 percent broke for Her Majesty. That jibes with what the AP found: “Among white Democrats, Clinton supporters were nearly twice as likely as Obama backers to say at least one negative adjective described blacks well, a finding that suggests many of her supporters in the primaries — particularly whites with high school education or less — were motivated in part by racial attitudes.”

2. Unless I’m missing something, the crosstabs don’t include data by party or, more importantly, data on white Democrats who are voting for Obama versus those who aren’t. For party results, you have to rely on the sidebar graphic that accompanies the article; white Republicans consistently score lower than white Democrats on racial questions, incidentally. The only data I can find on racial attitudes among white Democrats is in the scraps near the end of the interactive at-a-glance feature. There are some amazing gaps between white Dems who support Obama and those who don’t on certain racial questions — 30+ points in a few cases — but it’d be nice to compare their answers on all of them to see if the margins are huge across the board. If they’re not, it undermines the argument that racial attitudes are a significant contributing factor, or at least refines the question to ask which racial attitudes, specifically, are the killers.

3. Not all of the questions used as a gauge of negative racial attitudes unambiguously prove negative racial attitudes. E.g., “Agree or disagree: Irish, Italians, Jewish, and other minorities overcame prejudice and worked their way up, blacks should do the same without special favors.” Respondents could be interpreting “special favors” to mean affirmative action, in which case all they’re doing is answering whether they support AA. Is it racist not to do so? The nutroots would say yes, the rest of America wouldn’t.

4. I’ll quote Nate Silver for this one: “A related and unresolved question is how many persons will vote for Barack Obama because he is black. Such behavior would probably be more implicit and harder to ascertain than voting against a candidate because of racial prejudice. For instance, Obama’s biography is significantly more compelling because he is black (actually, bi-racial), and his change message is probably somewhat easier to sell because he looks different than other (e.g. white) politicians. If he were white, in other words, Barack Obama would not be Barack Obama. Moreover, there may be some people who explicitly vote for Obama because they think it will advance a goal of racial equality, present a different face to the world, and so forth. In the absence of sufficient detail on the study’s methodology, it is impossible to know whether these things have been accounted for.”

5. Related to the last point, not that it’s any comfort to Obama or any excuse for those who are voting for prejudiced reasons, per James Joyner there are worse liabilities to have as a candidate than the “wrong” race. Unfortunately, The One may be suffering on that account, too:

6. Finally, what do we make of this Rasmussen poll from last month? Obviously it’s not race per se that’s a dealbreaker or else McCain wouldn’t be getting his ass handed to him there. It’s the stereotypes associated with race, which Powell somehow transcends in ways that Obama evidently doesn’t. Is it his military record? Or his years of experience as SecState?

And with that, I hand the analytical baton to you.